Mobile devices conventionally have either a physical keyboard/keypad or a virtual keyboard/keypad that is selectively displayable on a touch-sensitive screen. In the former case, the physical keyboard/keypad occupies a significant proportion of the available frontal space on the device. Virtual keyboards, when displayed, also tend to occupy a significant proportion of the screen. One solution has been to provide the device with a slide-out keyboard but this adds girth, weight and complexity to the device. Another solution has been to provide the device with either smaller keys or fewer keys. Devices with keys that are too small make typing challenging. Devices with fewer keys than a minimal QWERTY keyboard (i.e. having multiple characters selectable by the same key) are generally not ergonomic for typing. Thus, there remains a real need for a user interface technology for mobile devices that addresses this technical problem.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.